Can fluid respect soft bodies (or any deformation!) in blender?
In short, no. The fluid sim won't interact with any other simulator. But there is a way around this limitation.

For the obstacle object, selected Export Animated Mesh, this will animate the mesh itself, rather than simulating the mesh. As a "real" mesh, the fluid sim will treat it like any other mesh, and react to it appropriately. However, this will have to be repeated anytime you want to change the physics simulation. Incidentally, this also means that the soft-body cannot react to the fluid sim.